Heretofore, comparison functions have been employed to classify input symbol bit maps against a library of character template bit maps. The summation of all of the pixel comparisons in each of the input/template correlations produced correlation values which revealed the closest match. However, these prior correlation techniques did not employ a comparison inequality function and underlying "Exclusion Inequality Principle" for excluding low correlation templates in order to accelerate the classification process. Nor did these prior art techniques employ pixel intensity sorting and pixel discrimination sorting.
U.S. Pat. No. 5,379,349, issued Jan. 3, 1995 to Hadar Avi-Itzhak (Ser. No. 07/937,732, filed Sep. 1, 1992 by the present assignee) entitled METHOD OF OCR TEMPLATE ENHANCEMENT BY PIXEL WEIGHTING, teaches the use of a comparison function to enhance a library of character templates with respect to a particular font or variation range of the input symbols.
Ser. No. 08/008,556, filed Jan. 22, 1993, now abandoned by the present assignee entitled METHOD OF MULTI-FONT TEMPLATE ENHANCEMENT, teaches enhancement of library character templates with a provision for template sub-classes to accommodate multiple representations of each input symbol.
Ser. No. 08/062/830, filed May 17, 1993, now abandoned by the present assignee entitled A COMPARISON FUNCTION BASED METHOD OF ACCELERATED NEAREST NEIGHBOR OCR CLASSIFICATION, teaches the use of the "Triangle of Inequality Principle" in order to exclude distant templates and accelerate the classification process.